Substrate structure-activity relationships guide rational engineering of modular polyketide synthase ketoreductases.
Substrate structure-activity relationships guide rational engineering of modular polyketide synthase ketoreductases.
复制标题
DOI：
10.1039/c5cc07315d
复制
发表时间：
2016-01-14
期刊：
影响因子：
--
通讯作者：
Keatinge-Clay AT
中科院分区：
文献类型：
--
作者：
Bailey CB;Pasman ME;Keatinge-Clay AT
模块化聚酮合成酶酮还原酶可以通过一次还原设置两个手性中心。为了探讨立体调控的基础，研究了三种α-甲基、β-酮硫酯底物和四种酮还原酶的构效关系。由于发现与β-酮酰基片段的相互作用是最关键的，因此与该片段接触的残基发生了突变。两个突变足以完全逆转模型酮还原酶EryKR1的立体选择性，将其从产生（2S,3R）产物的酶转化为产生（2S,3S）产物的酶。
Modular polyketide synthase ketoreductases can set two chiral centers through a single reduction. To probe the basis of stereocontrol, a structure-activity relationship study was performed with three α-methyl, β-ketothioester substrates and four ketoreductases. Since interactions with the β-ketoacyl moiety were found to be most critical, residues implicated in contacting this moiety were mutated. Two mutations were sufficient to completely reverse the stereoselectivity of the model ketoreductase EryKR1, converting it from an enzyme that generates (2S,3R)-products into one that yields (2S,3S)-products.